Thread: B-14 Panhard bar conversion (lots of pics)

How I did it.


First, a warning. I will take no responsability for what you decide to do to your car. If you do not know how to fabricate, do not do this yourself. Do not ask me to do this mod to your car as I will have to decline (I do not enjoy working on other people's cars). If you do not know how to weld, do not do this yourself. I will post enough info here that you should be able to take it to a good fabricator and they will be able to figure out what to do.

I will be more than happy to answer any questions you may have about the conversion process. That is why I am posting here on the forum for everyone to see.

Remember, this is my version of how to install a panhard bar on a B-14. My hope is that it may inspire someone else to come up with thier own version that may be better than mine. At the very least I hope that this can become an invaluable reference to anyone who is even mildly interested in a panhard bar conversion as the info up to this point has been a bit elusive.



Now to the why, as in, why did I decide to do this conversion. Well, a couple of months ago I took the SE-L to Sebring for a track day. In case you did not know, Sebring is known for being a bumpy track, especially in turns 1 and 17. It was in these turns that I noticed something funny. The car acted very oddly. It was like the front end of the car and the back end of the car were not connected. Each end went through the turns in it's own way. This was not a very comfortable feeling especially in turn 1 which is a high speed (80mph+) blind left hander. I knew instantly that the Scott-Russell Linkage (SRL) was to blame as I had read about it previously (thank you Mike Kojima). I knew that this had to change before I went to another track day.

My setup;

280,000+ mile chassis
KYB AGX front struts/rear shocks
Road Magnet progressive rate springs
Progress adjustable front sway bar
Progress rear sway bar (non adjustable)
Stillen FSB
Generic RSB
SR20VE with N1 cams
B-15 5speed VLSD(with terabley vague shifter, blah!)
SSAC header (I think) with 2.5" collector
Hodge-Podge exhaust that ends with 2.25" piping to a Subaru STI muffler (wtf? )

All of this stuff was on the car when I bought it.


For the track day I was using 15x7 +35 wheels with Continental Tire slicks (one heat cycle take-offs from one of the Continental Tire Challenge Mini race teams)
For the street I use 17x7.5 +40 with Yokohama S-Drives that are currently very worn.


The reseach I did consisted of searching Google for B-15 panhard bar. I am not going to post all of those links because it will be easier for you to open another browser page, go to Google and do your own search. I found a lot of stuff from 2J Racing Shop. Mike Kojima's Moto IQ article on his B-15 race car was also a great source of info, i.e. photo insperation.

There is one link I will post,

RPM Net Tech Articals: Understanding Coil Springs - Powered by: AFCO

If you are considering this panhard bar conversion, go to that link and save it in your favorites right now! If you read it and don't understand it, read it again. And again. And again! I have read it several times. It is good stuff.



As far as fabrication goes, it probably took me about 16 hours over 4 days. This was all done in my driveway with basic fabrication tools;

4.5" grinder
sawsall
drill press
cordless drill
Millermatic 211 wire feed welder (GMAW-S, Agon/CO2)
tape measure
silver pencil
sharpie
speed square
and all of the required PPE, because I hate having shards of metal in my eye!

I will not rate the fabrication on a scale of 1-10 because I have been fabricating professionially since 1996. So my scale may be different than your scale. I did not consider any of this to be very difficult, but it does take some time.

We will get to the nitty gritty in the next post!

Super sub'd thank you in advance

Awesome, hope to read more from you! I'm already reading the articule you indicated there!! Thanks!

Damnit!!!! I just had a bunch of stuff written and IE locked up on me and I lost it!

Now I have to start over.

Please bear with me.

Damn that is frustrating. I will have to do more posts with less info in each one so that does not happen again.

I ordered my rod ends from Rockkrawler 4 link kit, bearing, heim joints, heims, joint, jam nut, supply, rod ends. I found them on ebay.

Part # 370436409707

1/2" x 1/2-20 chromoly panhard bar kit .065 bungs heim

Each set comes with two rod ends (one left hand thread and one right hand thread), two jam nuts and two weld in bungs for 1"o.d. .065" wall tubing. The opposite thread makes adjusting the bar easy.

I ordered two kits. One for the panhard bar and the other for the diagonal brace for the chassis mount.

For the chassis mount I decided to use some 1" x 2" x 14ga rectangular tubing. I also used this for the axle mount.



I drilled 7 holes that are 3/4" away from eachother on the chassis mount. The axle mount has 4 holes with the same spacing.



The rod end fits inside the rec tube with room to spare. Spacers are needed. I used 1/4" washers that I drilled out to 1/2". Two spacers on each side of the rod end made for a perfect fit. A 1/2-13 x 2" grade 8 bolt is used to lock the rod end in place. Remember, you want the center of the rod end to be tight to the bolt. That part should not move once the bolt is tightened.

The chassis mount has more holes for two reasons. One, the chassis side of the panhard bar will almost always be higher than the axle side. Two, the diagonal brace would need to mount above the panhard bar in whatever position the panhard bar is placed.

Another note on the diagonal brace. If you have done your research you will probably have noticed that most diagonal braces are welded on to the chassis mount above the highest hole with the opposite end welded to the frame rail on the other side of the car. While that is a proven solution, I figured that the chassis mount would be stronger the closer the diagonal brace attaches to the panhard bar. So by making the diagonal brace and adjustable length rod, I will be able to mount the brace close to the panhard bar and keep a strong connection. And as you will see, it leaves more room for the exhaust.

Type it all up in Notepad, or another offline editor, and when you're all ready, copy/paste it into the forum message box. It's allot easier than doing it in that little box when typing more than a few sentences.

C

So now I had to figure out where to attach the chassis mount. I noticed that most of the cars that have had this modification have had the chassis mount on the right side of the car. Mine is no different. There is just too much gack on the left side with all of the evap crap in the way as well as the fuel filler neck etc...

So the frame rail is an obvious choice to locate the chassis mount but I did not just want to tee it up to the bottom of the rail. A tee connection would not offer the rigidity that I was looking for. It would be much better to use a side of the frame rail too. So on the wheel well side of the frame rail (outside), there is a box shape section of sheet metal that defines the upper part of the wheel well. I thought that this would make a nice attachment point as I would be able to catch that, plus the frame rail on the side and bottom. That would make for a very strong connection. Here is what I am talking aobut



I had to trim the sheet metal a bit with my sawsall so that there was a straight line across (horizontal plane) the bottom. These pictures also show where I have removed the undercoat and paint in preparation for welding.

Next is the mounting plate. Just like a roll cage, you need to have a mounting plate to gain surface area when attaching to the thin factory steel. I started with the top plate that connects to the bottom of the wheel well. Then I had to trace the bottom edge of the frame rail since it has a curve in that location. Then I made the plate that covers the bottom of the frame rail. Here is what it looks like.







I held the parts up to the car when I tacked them together. I did this because the plates are not all 90 degrees from eachother. It fits pretty well!





I welded the plates together off of the car before attaching it. And here it is all welded up in place.





As you can see, there is a lot of weld holding this plate to the car. That is a good thing!

So attaching the chassis mount to the mounting plate is a bit of a challenge as there are multiple angles that need to be accounted for. First off, the chassis mount needs to be parallel to the axle, plus it has to be perpendicular to the frame rail. It is important to get the measurements correct as well as the marks needed to locate everything. Remember, it is a good idea to be conservative with your cuts because it is easier to cut more off than to try to add some back!!

Also, to get the length of the chassis mount correct, I had to raise the axle up to ride height. This also helps with spacing the mount away from the axle.

This is what the chassis mount looks like after I cut it to fit the mounting plate.



As you can see, it is not a simple cut.



But the fit was spot on.



Three seperate planes of attachement make for a strong connection!





I spaced it aproximately 1-5/16" from the axle. Remember that the tube is less than 1" thick when the bolt is tight and I am using 2" bolts. The clearance is pretty tight.

Now that the chassis mount is finalized, I can work on the axle mount. One of the benifits of placing the chassis mount on the outside of the the frame rail is that it makes the panhard bar longer.

So the first step is to find the center line of the axle. Nissan placed a nice little hole right on center so that it is easy to find, but you will want to be a bit more precise and mark an actual line. The next step is to measure the distance between the center line on the axle and the center of the bolt holes on the chassis mount. Then mark that measurment on the other side of the axle. That is where the center of the axle mount holes should be. Remember to do this measurement with the axle at ride height. By doing this, you assume that Nissan has centered the axle when the car is at ride height. I know that is a lot to assume, but it is probably close enough and if need be you can adjust the length of the panhard bar on an alignment rack to center it up in the future. But I am not losing any sleep over it.

So here is the axle with my marks on it for locating the mount. The line all the way to the inside is where the center of the holes will be. The line just outside of that is the back edge of the tube and where tube backing plate will attach to the axle. You can see that there is a piece of steel welded to the top of the axle tube with a nice fat bead right where I need to place my mount.



So I clearanced the plate accordingly



I used some pieces of 1.5" x 3" x 14ga tube and some 1" x 1" x 14ga square tube to make the bracing for the axle mount.









And then I welded it all up and welded it to the axle.